fix(mmi): improve mmi controller unit tests (#25031)

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## **Description**

Add more unit tests in the mmi controller to increase coverage

## **Related issues**

Fixes:

## **Manual testing steps**

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- [x] I've completed the PR template to the best of my ability
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## **Pre-merge reviewer checklist**

- [x] I've manually tested the PR (e.g. pull and build branch, run the
app, test code being changed).
- [x] I confirm that this PR addresses all acceptance criteria described
in the ticket it closes and includes the necessary testing evidence such
as recordings and or screenshots.